function s1_goto_dir(){

	cd "$1" || exit 1
}

function s2_touch_empty_file_with_given_name(){

	touch "$1"
}

function s3_make_directories(){

	mkdir projects

	cd projects

	mkdir git

	mkdir backup

}

function s4_create_6_files(){

	touch projects/linux{1,2}_{centos,redhat,c_programming}


}


function s5_make_directories_in_git(){

	mkdir projects/git/linux1 projects/git/linux2

}

function s6_move_files_to_dir_1_or_2(){

	mv projects/linux1_*projects/git/linux1/
	mv projects/linux2_*projects/git/linux2/
}

function s7_create_package_and_copress(){

	cd projects

	tar -czvf backup/git.tar/.gz git/
}

function s8_delete_dir_git(){

	rm -rf projects/git/
}


function s9_recover_from_git_tar_gz_bakeup(){

	tar -zxvf projects/backup/git.tar.gz -C ./projetcts/

}

function s10_create_package_and_compress(){

	cd projects

	tar -jcvf backup/git.tar.bz2 git/
}

function s11_find_and_sort_alphabetically_all_created_files_and_dirs(){


	find ./projects -type f -o -type d | sort

}

function s12_get_next_15_minutes_boundary(){

	courrent_timestamp=$(date +%s)

	rounded_timestamp=$(( (current_timestamp + 750) / 900 * 900 ))

	current_timestamp=$(date +%s)


	
	interval_start_timestamp=$(( (current_timestamp / 900) * 900 ))

	next_interval_timestamp=$(( interval_start_timestamp + 900 ))

	next_15min_boundary=$(date -d @"next_interval_timestamp" +%Y-%m-%d_%H:%M:%s)

	echo "$next_15min_boundary"

}


























